Question

83. Why is the Indian Sunderbans steadily losing its famed mangroves?

• A. Prop roots of the mangrove trees are increasingly being cut by local communities to construct impermeable fencing against attacks by an increasing population of tigers.
• B. There is less fresh water flow, while the rate of sea level rise is increasing.
• C. Over-fishing is depriving the mangroves of its natural eco-balance.
• D. Dumping of toxic material into the river waters in Bangladesh find their way into the Indian side due to the mild variation in elevation of the entire Sunderbans

Answer 1

The correct option is B There is less fresh water flow, while the rate of sea level rise is increasing.

How climate change and sea level rise has contributed to the phenomenon of losing land, including mangrove forests in the Sundarbans, in the last part of the 21st century: This is because there is less fresh water flow and sediment supply in the western (Indian) part of the delta, so we have starvation of sediment and the rate of sea level rise is higher than sediment supply. Hence we are losing land, including mangrove forest.
The eastern (Bangladesh) side of the delta is gaining land because of the huge amount of sediment and water flow from the Brahmaputra and Meghna rivers.